With the advent of television programs such as America's Most Wanted and the proliferation of the Internet, it has become easier for members of the public to assist law enforcement in apprehending potential lawbreakers. It has been well-established that the prospects for apprehending a criminal is the greatest during the earliest time period following a crime. It is during this time when the criminal is in flight. The need for improved criminal detection systems is particularly urgent in view of the events of Sep. 11, 2001 and the prospect for future acts of terrorism. It has been repeatedly shown that citizen participation is of great assistance in law enforcement. The critical shortcoming has been to provide a system which can be quickly provided to the public to materially assist law enforcement.
There have been a number of patents directed to the area of alert systems. U.S. Pat. No. 6,543,051 discloses a system for inputting conventional emergency alert messages, such as tornado or flash flood warnings, into a digital subscriber television system. The method allows existing emergency alert equipment to interface with the digital system equipment in the headend of a digital subscriber television system. A unique identifier and the format of the digital emergency alert message allow the input of an emergency alert message and allow for a wide variety of optional data formats, system control options, and data storage options.
U.S. Pat. No. 6,498,627 discloses a brevity signaling module for a digital television (DTV) receiver enables the reception of emergency broadcast messages. The overlay signal received at the receiver front end is squared in a squaring loop, producing spectral lines at DC and twice the overlay signal frequency, or 2.omega., where .omega.=2.pi.f and f is the center frequency of the overlay signal. The squared signal is passed through a narrow band filter having a bandwidth sufficient to pass a spectrum containing a plurality of tones 2.omega., 2.omega..sub.1, 2.omega..sub.2, . . . , 2.omega..sub.n, where 2.omega..sub.1, 2.sub.2 . . . , 2.omega..sub.n are different frequency tones assigned to different auxiliary functions. The detected tone is used by a control module to determine whether normal multi-path processing should be performed or whether this processing should be suppressed and auxiliary functions performed, including turning on the DTV receiver power in order that an emergency broadcast message might be conveyed to persons in the vicinity of the DTV receiver.
U.S. Pat. No. 6,204,761 discloses a weather alert system to warn a user when an emergency signal has been broadcast and to simultaneously activate a television or other visual information source and to select a predetermined informational channel. The weather alert system includes a signal detector for detecting a broadcast alarm signal and for generating an activation signal upon detection of the alarm signal. A remote controller is operatively connected to the signal detector for producing a remote control signal in response to said activation signal. The remote control signal is utilized to trigger the activation of a visual information source such as a television or a computer to provide visual information relating to the hazardous condition.
U.S. Pat. No. 6,543,051 discloses a geographically specific emergency alert system, principally directed to weather alerts, including a code generator unit in which geographic areas to be alerted and types of severity of alerts are selected and code strings generated to represent the affected areas and alert types selected. The code strings are broadcast by modulating the audio carrier of a television signal and received on receiver units positioned in areas within the broadcast market of a television station providing the alerting service. Location codes or entered into the receiver units by the users according to the areas in which the receiver units are used. When an alert is broadcast, each receiver unit decodes a location code string in the signal. If it matches that set on the receiver, an alert code string is decoded to activate an alarm devices connected to the receiver, such as an audible alarm generator, LED, etc., in accordance with the type or severity of alert that was broadcast.
U.S. Pat. No. 4,155,042 discloses a disaster alert system which consists of two major sub-systems. The first sub-system is a central disaster alert station which transmits coded R.F. activation signals specifying the geographic area and/or the official personnel to be alerted. Said central disaster alert station also transmits audio signals containing the disaster warning message to be disseminated to potential disaster victims and/or pre-selected official personnel. The second and companion sub-system consists of a plurality of independent and remotely located disaster alert modules which can be placed in any location to which disaster alert information is to be disseminated. Said disaster alert modules operate on continuous low-power standby, receiving and analyzing R.F. signals of a pre-determined carrier frequency and bandwidth. In the absence of said coded activation signal, said disaster alert modules remain in low-power standby. Detection and decoding of said coded activation signals results in activation of the module main power circuits. Activation of main power circuits results in a plurality of module outputs, including but not limited to, production of a clearly audible alarm signal, display of a clearly visible alarm signal, reproduction of the audio message, and activation of desirable auxiliary units equipped with said modules, such as, but not limited to, television receivers, public address systems, and civil defense sirens. Specially designated disaster alert modules located on or near roadways produce, upon similar activation, conspicuous alarm signals, and display disaster alert information on road signs. Said disaster alert modules operate on self contained battery power with means provided for continuous or occasional re-charging from A.C. lines. Said disaster alert modules remain operative in the event of A.C. power failure. The low-power standby mode is intended to conserve energy and maintain extended battery life, and to preclude discernible outputs when no disaster conditions exist.
While there have been a number of systems for alerting or warning the public of criminal matters and the like, there have been no effective systems for permitting criminal warnings to be widely broadcast at a point in time where the information can be widely and immediately disseminated to the public to maximize assistance to law enforcement.